This invention relates to an apparatus for manufacturing a ferromagnetic product having improved abrasion resistance.
Recently, magnetic recording products, such as magnetic tape, a magnetic disc or the like have been produced which have an excellent high-density recording property and which are obtained by vapor deposition of a magnetic film of metal or metallic oxide of the surface of a non-magnetic substrate made of synthetic resin or the like. The deposition films include obliquely incident vapor deposited type magnetic film, a Co-Cr vertical deposited type magnetic film, Co-Ni-P plated magnetic film, a -Fe.sub.2 O.sub.3 sputtered magnetic film, a BaO-Fe.sub.2 O.sub.3 sputtered magnetic film.
In order to improve an abrasion resisting property of the magnetic film, the inventors of this application have proposed previously a method of manufacturing an improved abrasion resisting magnetic recording product, wherein a vapor deposited coating film of a lubricant of higher fatty acid or metallic salt thereof is formed thinly and firmly on the magnetic film of the magnetic recording product by a vacuum vapor deposition step. (Japanese Patent Application No. 19615/Showa 53 (1978) and Japanese Patent Application No. 62279/Showa 53 (1978)). The inventors, however, have found that there is a relationship between the condition of the surface of the magnetic film and the adhesion strength of the vapor deposition film of the higher fatty acid or metallic salt thereof to the magnetic film. This relationship is especially important when the magnetic film has been exposed to atmospheric air, which results in moisture, N.sub.2, dusts or any other contaminating substance in the air being adhered to the surface of the magnetic film. If the magnetic film surface with such contaminants thereon is coated by the vacuum vapor depositing the lubricant, the abrasion resistance of magnetic recording product with the deposited coating film of the lubricant thereon is lowered, because the adherence strength of the deposited coating film of the lubricant at the contaminated surface portions of the surface of the magnetic film, as well as the whole surface of the magnetic film, is lowered and the deposited coating film of the lubricant peels off easily.